Last weekend began so well. You were tearing up the court, playing your best tennis in years. You charged the net and whammo, crunch, pop—there went the ankle.

You're bummed, your ankle's trussed up and aching, and you're supine for a couple of days, mentally replaying the game over and over again with a ton of "what ifs."

But hey, stop beating up on yourself.

That's what physical therapists are for.

These professionals are licensed to inflict pain and torture in the name of good health and better mobility. They pummel, massage, knead, and repurpose the bones and muscles of the sick, the injured, and the disabled of the Earth. That physical therapist—also called by many of their charges, through teeth clenched in pain, "physical terrorists" or "PTs"—can, if you're lucky, whip you and your ankle back to mobility sooner than you can say "Smash!," "Bang!," and "Pow!"

Physical therapy supposedly has been around since the ancient Greeks, with Hippocrates lionizing massage therapy and Hector, another Greek doc, pushing water therapy. Modern PT got a boost in the U.S., when a school opened in Washington, D.C., to use physical therapy techniques to help soldiers wounded in World War I. Polio outbreaks, beginning in the 1920s, impelled the expansion of physical therapy, eventually expanding from hospitals into outpatient clinics and further specialization.

The goal of physical therapists is to jack up the strength and flexibility of patients who have reduced mobility because of an injury, illness, or disability. This is a laudable goal for people who are in a "helping" profession. But often, the patient can lose sight of this goal as their physical therapist goads him into doing "just one more leg" extension when the patient, who's just endured a knee replacement, can't think beyond the timing of his next pain pill.

PTs need to be in good shape themselves because they spend the bulk of their days standing, squatting, bending, and otherwise giving their muscles a serious workout as they lift, position, and manhandle patients for the greater physical good. They'll be busy overseeing exercises and exercise equipment, stretching maneuvers, hands-on therapy—all of which are very physical (hence, the "physical" in "physical therapy").

When they're not poking and prodding, the PT will be devising and modifying the plan of action for the patient, assessing a patient's progress, and checking out new treatments.

And it's important that PTs love humanity and can't think of anything better to do with their time than cheer their patients on. PTs are a lot like coaches—they're there to encourage, motivate, and spur on patients to tackle exercises that can be excruciatingly painful. This is a challenge in itself. The more pain they endure, the more patients remind themselves of what they used to be (usually healthier) and what they are now (physically impaired).

This is not a recipe for good moods and happy campers. Often, patients yell not only at the exercise machine, but also at the hapless PT who's making them exercise in the first place. So it's important for PTs to be patient and compassionate and thick-skinned.

What about that patient who calls a hapless PT everything in the book, including "Anti-Christ" and "spawn of Satan" as the PT makes him raise his bad arm to strengthen it after rotator cuff surgery? Naw, no problem; a PT can't take this explosion of rage personally.

Remember, PTs go into physical therapy to help people, even if, at first, the patients don't know what's good for them. Also, PTs remind themselves that patients typically progress one baby step at a time. "Quick results" have no place in the world of physical therapy.

PTs come in all sizes, shapes, and colors, and toil in just as many specialties. Some stick with hospitals, medical clinics, and nursing homes; others work in private offices, like sports medicine clinics. Still others are their own bosses, owning their own practices.

No matter where PTs work, the phrase "there's no 'i' in 'teamwork' " is the truth. Loners don't last long as physical therapists because PTs are usually part of a health care team that includes PT assistants and aides, doctors, surgeons, and others. They devise programs (which usually have words like "fitness" and "wellness") to encourage healthier, more active lifestyles.

Training involves more than acing "Brute Force 101." Studies involve heavy-duty subjects like biomechanics, calculus, statistics, chemistry, and nutrition. Academic requirements aside, PTs may have to do fieldwork (where, what, and with whom? It's up to instructor's discretion). And before PTs work over their first patient as a professional, they have a bachelor's degree (or more) and a state license. That's a lot of academic work to work in a field that involves a lot physical work.

If PTs want to specialize, that means more credentialing in one of the eight official specialties listed by the American Board of Physical Therapy Specialties: cardiovascular and pulmonary (heart, lungs, breathing); clinical electrophysiology (electrical impulses, muscles, bones, wounds); geriatric (all things old folks); integumentary (skin, but mainly wounds and burns); neurological (nerves); orthopedic (bones); pediatric (kids); sports (athletes); and women's health (childbirth).

The money can be good, with the median income hovering around $75,000 a year and the top ten percent of wage earners raking in more than $100,000 (source). Depending on ambition, work ethic, energy, and ability to make a buck, PTs can own and operate small or large physical therapy chains (as in "stores," not "physical restraints"). One chain is in more than 200 locations in the U.S.

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